| Methods |
Setting: local communities with lung associations, USA
Recruitment: media advertisements for American Lung Association (ALA) self‐help materials |
| Participants |
1237 smokers who completed a questionnaire and paid a refundable deposit |
| Interventions |
No face‐to‐face contact
∙ ALA leaflets (8 leaflets including 2 brief cessation brochures: Me Quit Smoking? Why? and Me Quit Smoking? How?)
∙ Leaflets and maintenance manual: A Lifetime of Freedom from Smoking
∙ Cessation manual: Freedom from Smoking in 20 Days.
∙ Cessation and maintenance manuals |
| Outcomes |
Sustained abstinence at 12 months (point prevalence at all 5 follow‐up points); self‐report in a telephone interview
Validation: none |
| Notes |
2 plus 3 plus 4 vs 1, self‐help vs leaflet only |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
Randomised; method not described |
| Allocation concealment (selection bias) |
Unclear risk |
No details given |
| Blinding (performance bias and detection bias)
All outcomes |
Low risk |
No biochemical validation used but no personal contact; interventions all of similar intensity, so differential misreport judged unlikely |
| Incomplete outcome data (attrition bias)
All outcomes |
Unclear risk |
No information on number lost; all randomised participants included in ITT analysis |
